Woven fabrics having a plurality of miniature holes or openings generally defined by the spaces between the interlaced threads or yarns have been used as acoustical material on partitions, wall boards, and the like, as between work stations in an office area. The acoustical material made from a woven fabric having a plurality of miniature holes or openings have been generally laminated to an acoustical backing or substrate (typically fiberglass webbing or plastic foam) which is then fastened near the edges of the wall board or partition using clips, nails, tacks, or the like.
The plurality of holes or openings in the face fabric absorb sound and are therefore essential to the acoustical characteristics of the fabric. However, the holes prevent conventional acoustical materials comprised of woven fabric from being used as an ordinary wall covering. Conventional use of the known woven acoustical fabrics with typical wall covering paste is impractical because the paste would flow through the openings, thereby at least partially filling the holes and reducing the ability of the fabric to absorb sound, as well as defacing the exposed decorative surface of the fabric.
Attempts to avoid this problem and provide an acoustical wall covering comprising a woven fabric having a plurality of sound-absorbing holes and which can be pasted to a wall using conventional wall covering paste have been generally unsuccessful.
One way to solve the problem is to form a lamina or plied structure comprising an impermeable thermoplastic backing secured to an acoustic woven fabric. While the impermeable backing will prevent the paste from flowing through and filling the holes in the woven fabric, it also prevents air and moisture from passing through the lamina or plied structure, which severely retards the rate at which the paste will dry and, consequently, promotes or at least facilitates the growth of fungus and molds, whereby unpleasant odors may be generated.